Vehicle tires suffer wear and must be monitored for tread depth so that they can be changed when wear exceeds specified standards. While this may seem like a simple process (e.g., walking to each tire and measure the depth with a depth gauge), this manual process is imprecise, prone to errors, and relies completely on the diligence of the measurement taker. Additionally, checking and recording information for 18 tires on a typical tractor-trailer can take a significant amount of time. This is particularly true if this monitoring is desired by a large fleet (such as FedEx or UPS) each day as the fleet leaves the distribution point.
A number of techniques have been proposed or suggested for the measurement of tire tread depth. Laser scanners than can capture a profile of an object are well known in the scanning industry. These scanners can quickly capture a profile of an object such as a tire and therefore provide information about tread depth. Existing systems, however, required the tire to be scanned face on and therefore required the scanner to be placed either directly under the tire or to be moved into the path of the tire to take the measurement and then moved out of the path as the tire moves forward. Such designs therefore required significant moving parts, an operator (or robot) to move the scanner or required the scanner to be ruggedized to allow the tires to roll over the scanner without damaging the sensor or any materials that the scanner had to see through to perform its scan.
A need exists for improved methods and systems for evaluating tread depth, such as evaluating all 18 tires on a slowly moving tractor trailer. A further need exists for improved methods and systems for evaluating tread depth that reliably gather the information without manual intervention by the driver or an operator and enter this information into a database for current and future use. Yet another need exists for improved methods and systems for evaluating tread depth that are sufficiently rugged to be able to function in the real world (at truck stops and fleet distribution yards) in the harsh environment found in the trucking industry.